Electrical connector



April 27, 1948. HECIHT 2,440,270

BLECTRI CAL CONNECTQR Filed July 3, 1946 2 Sheets-Sheet 1 I... I I I I70mm s A I INVENTOR By RA. HECl-IT April'27, 1948. R. A. HECHTELECTRICAL CONNECTOR Filed July 3, 1946 2 Sheets-Sheet 2 8 mun 3 L xEY-IJIHIIIHHI T Q? m 6 3 m 4 m I u.. u 1 FT k 0 W K 4 a 3 3.

INVENTOR' RA. HE CHT ATTORNEY Patented A r. 21, 1948 ELECTRICALCONNECTOR Rudolph A. Hecht, Teaneck, N. J., assignor to Bell TelephoneLaboratories,

Incorporated,

New York, N. Y., a corporation of New York Application July 3, 1946,Serial No. 681,202

13 Claims.

This invention relates to electrical connectors and particularly toterminal strips consisting of two cooperating terminal units which arearranged for quick separation.

In the field of electribal wiring the terminal strip plays a well knownrole. Its basic purpose is to facilitate the making and breaking ofconnections between a plurality of electric circuits and to otherwisesimplify the electrical connections of equipment involving a greatnumber of conductors. The conventional typeof terminal strip comprises aplurality of terminals rigidly mounted on an insulating block so as toextend therefrom in opposite directions, each terminating at each end ina conventional design of terminal tab to which wiring connections aremade. While this type of terminal strip serves its purpose it does notprovide the quick separable feature of connectors of the jack and plugtype which is desirable in cases where the connector is to be used withequipment constructed on a unit type basis.

The jack and plug type connector, though facilitating the quick removal.or substitution of equipment units from, and in an electrical system,is, in general, characterized by a sliding type of contact which issubject to failure due to opens and high resistance, contacts caused bythe collection thereon of dust and dirt. In a copending application,Serial No. 657,172, filed March 26, 1946, there is disclosed anelectrical connector which embodies the desirable quick separationfeature of the jack and plug type connector and, at the same time.precludes the possibility of contact failure. The connector of thatapplication comprises two cooperating 'terminal units, the correspondingterminal elements of which are soldered together under tension. Byvirtue of the soldered connections contact failures are eliminated. Toseparate the two terminal-units of this connector the solder is fused bythe application of a hot soldering iron to the points of connectionbetween the various contact members whereupon the terminal elementsspring apart and permit the quick removal of one, or both of theterminal units.

The object of this invention is to provide an improved electricalconnector of the type disclosed inthe above-identified copendingapplication.

The connector of the present application comprises two independentterminal units mounted in such a manner on a unitary supporting bracketas to be longitudinally displaceable relative to one another so as totension the contact springs of one unit with respect to the contactsprings of the other unit. The corresponding contact springs of the twounits are soldered together at their points of contact while in theirnormal un- 5 tensioned condition so that when the units are relativelydisplaced, the springs thereof are placed under relative tension andautomatically separate when a'hot soldering iron is applied to thesoldered connections and the solder fuses. When the force applied torelatively displace the two units is removed subsequent to the fusing ofthe solder, the contact springs resume their normal untensionedcondition without adhering to each other thus rendering possible thedisengagement of one unit from the other.

An auxiliary feature of the invention resides.

in the use of mutually engageable stops on the two terminal unitswhereby the extent to which the units may be relatively displaced ismain-- units are illustrated in their normal positions;

Fig. 2 is a fragmentary front view of the connector shown inFig. 1. Inthis view the upper terminal unit is shown longitudinally displacedrelative to the lower terminal unit and illustrates the springseparation caused by this dispacement after the solder has been fused;

Fig. 3 is a side view of the connector shown in Fig. l; V

Fig. 4 is a front view of a connector illustrating a preferredembodiment of the invention; and

Fig. 5 is a side view of the connector shown in 40 Fig. 4.

Referring particularly, at this time, to Figs.

1, 2 and 3 the connector disclosed therein com v-.prises essentially anupper terminal unit Iii, a

lower terminal unit U-shaped supporting bracket, or carrier 9. Asillustrated. each of the terminal units l0 and I2 comprises two blocksof insulating material arranged in superposed contiguous association.Obviously, instead of using two such blocks a single molded block may beemployed. Each insulating block of the unit III has moldedtherein aplurality of contact springs l3 which may be of any conventional designand which as illustrated, project in either direction at right angles tothe u longitudinal axis of the insulating blocks. The

I2 and a substantially contact springs l3 of the two blocks of the unitIn are arranged vertically, in staggered relation and horizontally, inalignment.

Each of the insulating blocks of the lower terminal unit i2 similarlycarries a plurality of contact springs I4 which are L-shaped in designwithv the forward: legsthereof extending vertically. The springs of thetwo insulating blocks of terminal unit l2 are also arranged vertically,in

passes through suitable apertures in the clamps The supporting bracket,or carrier 9 is a U- shaped sheet metal member whose opposite verticalsides are stamped, or otherwise formed into two legs l9 and I9. .Thetwo' legs i9 and I9 of each side of the bracket 9 occupy the samevertical plane, the leg l9 beingsubstantially rectangular in shape andthe leg i9 having an inverted U-shaped formation and arranged intelescopic relation to the leg i8. By virtue of the structural design ofthe bracket legs, legs 19 are relatively flexible whereas the legs l8are comparatively rigid. Each of the legs l8 and I9 is provided with aslot, or aperture 20 which accommodates one of the embossings ll of themolded blocks in and I2. The base of. the, U-shaped bracket 9 isprovided with holes such as 2| which accommodate screws or theirequivalent, by means. of which the bracket may be fixed to a support. 1

To assemble the connector just described, the clamps ii are slipp d overthe ends of the molded blocks l and I2 so that the embossings i1protrude through suitable apertures in the clamps. The turned-in edgesof the clamping brackets, i5 slide in the slots [6 in the insulatingblocks. The horizontally projecting portions of each of the brackets iiare pretensioned towards each other so that they firmly grip theinsulating blocks. The protruding embossings I! of the insulating blocksl0 and I2 are then fitted into their corresponding apertures 20 in, thesupporting legs 18 and I9 of the bracket 9. When the upper and lowerterminal units i0 and I2 are positioned on the bracket 9 the contactends of the springs l3 of the upper unit, which are tinned, make surfaceengagement with the pretinned contact ends of corresponding springs i lof the lower unit. These contacting points are then soldered together.In this normal condition of the connector the contact springs l3 and Hare untensioned.

When it is desirable to effect the separation of the soldered contactsprings, pressure is manually applied to the left leg i 9 (viewingFig. 1) in the direction of the arrow. The two oppositely disposed legsI9 and the terminal unit it) supported thereby are thus moved to theright until the stop 22 (Fig. 2) on the underside of the upper unitengages the stop 23 on the upper face of the lower unit. Due to therelative rigidity oi the bracket arms IS the lower terminal unit i2experiences little, if any movement when the bracket arms l9 are flexedas described. When themovement oi' the upper unit to the right. The

springs l3 of the upper unit being heavier and shorter than those of thelower unit do not experience any flexing due to the displacement of theupper unit. The contact springs i3 and I4 will, therefore, be placedunder relative tension at their solder points of contact so that when ahot soldering iron is applied to the solder at these points and thesolder fuses, the springs will separate and resume their normaluntensioned conditions. The relative positions of the contact springsunder this condition are shown in Fig. 2. When the fused soldersolidifies on the spring ends after the springs have become separatedthe pressure on the left bracket leg I9 may be released whereupon thelegs l9 and the terminal unit l0 return to their normal untensionedpositions.

It will be observed that while the connector of this invention is inuse, the soldered connections between corresponding springs i3 and II ofthe terminal units l0 and 12 are not under tension.

In the preferred embodiment of the invention illustrated in Figs. 4 and5, the support for the terminal units 30 and 3i is constructed of threeindependent elements. One of these elements consists of a base portion32 having two vertically extending legs 33 between which the lowerterminal unit 3! is supported. The other two elements are substantiallyinverted U-shaped and each comprises a horizontal bridging piece 34 andtwo vertically depending legs 35. The ends of the legs 35 are bentinwardly and are secured to the base 32 by means of rivets, or screws36. The material of which the base 32 and legs 33 are constructed isconsiderably heavier than the material of which the cross-piece 33 andlegs 35 are constructed thus giving greater rigidity to the lowerterminal unit 3| which is mounted on the legs 33. Thus any tendency thelower terminal unit may have to follow the upper terminal unit when thelatter is manually moved to the right in the connector shown in Figs. 1,2 and 3 is removed.

The insulating block of the upper terminal unit is provided with anupwardly projecting hand grip 31 by means of which the said terminalunit may be manually displaced relative to the.lower terminal unit.Also, each of the upper and lower arms of the clamping brackets 38 isprovided with a hole which accommodates a. surface boss ll near each endof' the insulating blocks of the two terminal units whereby the clampsare fixedly positioned on the blocks. Ifdesirable, the insulators ofeach unit may be molded as a single block, in which case the end clampswould not gether by fusible solder, and independently flexible supportsfor each of said units whereby said units may be relatively displaced torelatively tension the contact springs thereof at their soling asubstantially inflexible support for one of said units and a support ofgreater flexibility for the other of said units whereby said units maybe displaced relative to one another to relatively tension the contactsprings thereof at their soldered terminal ends.

3. The combination in an electrical connector of a carrier comprising abase, a pair of opposite- 1y disposed substantially rigid supportsextending vertically from said base, a pair of oppositely disposedflexible supports extending vertically from said base, a terminal unitremovably mounted between said first pair of supports, a terminal unitremovably mounted between said second pair of supports, contact springscarried by each of ble solder joining the contact ends of correspondingcontact springs of said terminal units.

4. The combination in an electrical connector as defined in thepreceding claim and in which the said pairs of oppositely disposedsupports are formed integrally with the base.

5. The combination in an electrical connector of a first and a secondterminal unit each having a plurality of contact springs, correspondingsprings of said units having their contact ends i said terminal units,and means comprising fusielectrically connected together by fusiblesolder,

and a carrier for said units comprising a base, a pair of substantiallyinflexible arms extending from said base and supporting said first unitin superposed spaced relation to said base, and a pair of flexible armsextending from said base and supporting said second unit in superposedspaced relation to said first unit whereby said second unit may bedisplaced relative to said first placement of said units comprisingmutually engageable stop members on juxtaposed faces of said insulatingblocks.

8. A two part electrical connector-comprising a support having flexiblearms, terminal units mountable between said arms, each unit comprising aplurality of contact springs, the contact springs of one of said unitsbeing connected to the contact springs Of the other unit by fusiblesolder when said units are mounted between the arms of said support, andsaid springs being tensionable in a manner tending to disengage themwhen pressure is applied to one of the flexible armsof said supportwhereby said springs become disengaged when the solder is fused.

9. An electrical connector comprising, in combination, terminal unitseach having a plurality of contact springs, the contacting ends thereofbeing held in permanent engagement by fusible solder, and a flexiblesupport for each of said units, one of said supports being movablerelative to the other support in a direction such as to tendto separatethe contacting ends ofsaid springs, thereby rendering said springsautomatically separable upon the fusing of said solder.

10. An electrical connector comprising, in combination, terminal unitseach having a plurality of contact springs, fusible means permanentlymaintaining the contact springs of one of said units in untensionedelectrical engagement with the contact springs of the other of saidunits, and independent supports for said units, said supports beingrelatively movable in a direction such as to tension the springs of oneof said units relative to the springs of the other unit whereby saidsprings automatically separate upon the fusing of said fusible means.

between a different pair oi. oppositely disposed for each of said unitswhereby said units may be displaced to relatively tension the contactsprings thereof at their soldered terminal ends, and means for limitingthe relative displacement of said-units.

7. The combination in an electrical connector of a flrst and a secondterminal unit each'comprising an insulating block carrying a pluralityof contact springs, corresponding springs of said units having theircontact ends electrically connected together by fusible solder, and a.carrier for said units comprising a base, a pair of substantially rigidarms extending from saidbase, and supporting said flrst terminal unit insuperposed spaced relation to said base and a pair of flexible armsextending from said base and supporting said second unit in superposedspaced relation to said first unit whereby said second unit may bedisplaced relative to said flexible arms of said support whereby saidunits are relatively movable in a direction such as to tension thesprings of one thereof relative to the springs'oi the other to rendersaid springs auto-- matically separable upon the fusing of said solder.

12. A two part electrical connector comprising a upport havingoppositely disposed pairs of flexible arms, terminal units eachcomprising a plurality of contact springs, and means supporting each ofsaid units between a different pair of oppositely disposed flexible armsof said support, the contact springs of said units being held inengagement by fusible solder and the arms of one of said pairs beingflexible upon the application of pressure thereto in a direction,relative,

at their soldered terminal

